Preboiling
Bring a pot of water to boil and briefly boil the beef chunks for about 5 to 7 minutes, or until a white foam forms at the top of the water. Drain dirty water, rinse beef shanks, and set aside.

Stir-frying
1. In the pressure cooker over medium high heat, saute garlic, ginger, scallions, and star anise in vegetable oil until fragrant.
2. Add beef shank pieces. onions, chili bean sauce and saute for a few minutes, until the beef is slightly browned.
3. Add soy sauce and cook for 2 minutes.
4. Add everything else!
5. Bring up to high pressure and cook under pressure for 25 to 30 minutes. Slowly release pressure and serve.